bus: properly handle if new objects are installed in the node tree while we are dispa...

[elogind.git] / src / journal / sd-journal.c

diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c
index 3aa9ed4b3275df6e9e2a82442f3e1125f6931a0e..3ccb14a242832fa2b4d0e0c903313d40004bed16 100644 (file)
--- a/src/journal/sd-journal.c
+++ b/src/journal/sd-journal.c
@@ -50,6 +50,15 @@
 
 #define DEFAULT_DATA_THRESHOLD (64*1024)
 
+static bool journal_pid_changed(sd_journal *j) {
+        assert(j);
+
+        /* We don't support people creating a journal object and
+         * keeping it around over a fork(). Let's complain. */
+
+        return j->original_pid != getpid();
+}
+
 /* We return an error here only if we didn't manage to
    memorize the real error. */
 static int set_put_error(sd_journal *j, int r) {
@@ -102,7 +111,8 @@ static void init_location(Location *l, LocationType type, JournalFile *f, Object
         l->seqnum_set = l->realtime_set = l->monotonic_set = l->xor_hash_set = true;
 }
 
-static void set_location(sd_journal *j, LocationType type, JournalFile *f, Object *o, uint64_t offset) {
+static void set_location(sd_journal *j, LocationType type, JournalFile *f, Object *o,
+                         direction_t direction, uint64_t offset) {
         assert(j);
         assert(type == LOCATION_DISCRETE || type == LOCATION_SEEK);
         assert(f);
@@ -110,12 +120,10 @@ static void set_location(sd_journal *j, LocationType type, JournalFile *f, Objec
 
         init_location(&j->current_location, type, f, o);
 
-        if (j->current_file)
-                j->current_file->current_offset = 0;
-
         j->current_file = f;
         j->current_field = 0;
 
+        f->last_direction = direction;
         f->current_offset = offset;
 }
 
@@ -164,7 +172,7 @@ static bool same_field(const void *_a, size_t s, const void *_b, size_t t) {
                         return true;
         }
 
-        return true;
+        assert_not_reached("\"=\" not found");
 }
 
 static Match *match_new(Match *p, MatchType t) {
@@ -178,7 +186,7 @@ static Match *match_new(Match *p, MatchType t) {
 
         if (p) {
                 m->parent = p;
-                LIST_PREPEND(Match, matches, p->matches, m);
+                LIST_PREPEND(matches, p->matches, m);
         }
 
         return m;
@@ -191,7 +199,7 @@ static void match_free(Match *m) {
                 match_free(m->matches);
 
         if (m->parent)
-                LIST_REMOVE(Match, matches, m->parent->matches, m);
+                LIST_REMOVE(matches, m->parent->matches, m);
 
         free(m->data);
         free(m);
@@ -210,6 +218,8 @@ _public_ int sd_journal_add_match(sd_journal *j, const void *data, size_t size)
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (!data)
                 return -EINVAL;
@@ -304,7 +314,10 @@ fail:
 }
 
 _public_ int sd_journal_add_conjunction(sd_journal *j) {
-        assert(j);
+        if (!j)
+                return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (!j->level0)
                 return 0;
@@ -322,7 +335,10 @@ _public_ int sd_journal_add_conjunction(sd_journal *j) {
 }
 
 _public_ int sd_journal_add_disjunction(sd_journal *j) {
-        assert(j);
+        if (!j)
+                return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (!j->level0)
                 return 0;
@@ -346,7 +362,7 @@ static char *match_make_string(Match *m) {
         bool enclose = false;
 
         if (!m)
-                return strdup("");
+                return strdup("none");
 
         if (m->type == MATCH_DISCRETE)
                 return strndup(m->data, m->size);
@@ -372,10 +388,8 @@ static char *match_make_string(Match *m) {
                         p = k;
 
                         enclose = true;
-                } else {
-                        free(p);
+                } else
                         p = t;
-                }
         }
 
         if (enclose) {
@@ -394,7 +408,6 @@ char *journal_make_match_string(sd_journal *j) {
 }
 
 _public_ void sd_journal_flush_matches(sd_journal *j) {
-
         if (!j)
                 return;
 
@@ -588,11 +601,14 @@ static int next_for_match(
                         if (r < 0)
                                 return r;
                         else if (r > 0) {
-                                if (np == 0 || (direction == DIRECTION_DOWN ? np > cp : np < cp))
+                                if (np == 0 || (direction == DIRECTION_DOWN ? cp < np : cp > np))
                                         np = cp;
                         }
                 }
 
+                if (np == 0)
+                        return 0;
+
         } else if (m->type == MATCH_AND_TERM) {
                 Match *i, *last_moved;
 
@@ -625,8 +641,7 @@ static int next_for_match(
                 }
         }
 
-        if (np == 0)
-                return 0;
+        assert(np > 0);
 
         r = journal_file_move_to_object(f, OBJECT_ENTRY, np, &n);
         if (r < 0)
@@ -731,7 +746,7 @@ static int find_location_for_match(
                         if (r <= 0)
                                 return r;
 
-                        if (np == 0 || (direction == DIRECTION_DOWN ? np < cp : np > cp))
+                        if (np == 0 || (direction == DIRECTION_DOWN ? cp > np : cp < np))
                                 np = cp;
                 }
 
@@ -811,7 +826,7 @@ static int next_beyond_location(sd_journal *j, JournalFile *f, direction_t direc
         assert(j);
         assert(f);
 
-        if (f->current_offset > 0) {
+        if (f->last_direction == direction && f->current_offset > 0) {
                 cp = f->current_offset;
 
                 r = journal_file_move_to_object(f, OBJECT_ENTRY, cp, &c);
@@ -827,7 +842,7 @@ static int next_beyond_location(sd_journal *j, JournalFile *f, direction_t direc
                         return r;
         }
 
-        /* OK, we found the spot, now let's advance until to an entry
+        /* OK, we found the spot, now let's advance until an entry
          * that is actually different from what we were previously
          * looking at. This is necessary to handle entries which exist
          * in two (or more) journal files, and which shall all be
@@ -871,6 +886,8 @@ static int real_journal_next(sd_journal *j, direction_t direction) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         HASHMAP_FOREACH(f, j->files, i) {
                 bool found;
@@ -889,10 +906,7 @@ static int real_journal_next(sd_journal *j, direction_t direction) {
 
                         k = compare_entry_order(f, o, new_file, new_offset);
 
-                        if (direction == DIRECTION_DOWN)
-                                found = k < 0;
-                        else
-                                found = k > 0;
+                        found = direction == DIRECTION_DOWN ? k < 0 : k > 0;
                 }
 
                 if (found) {
@@ -908,7 +922,7 @@ static int real_journal_next(sd_journal *j, direction_t direction) {
         if (r < 0)
                 return r;
 
-        set_location(j, LOCATION_DISCRETE, new_file, o, new_offset);
+        set_location(j, LOCATION_DISCRETE, new_file, o, direction, new_offset);
 
         return 1;
 }
@@ -926,6 +940,8 @@ static int real_journal_next_skip(sd_journal *j, direction_t direction, uint64_t
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (skip == 0) {
                 /* If this is not a discrete skip, then at least
@@ -966,6 +982,8 @@ _public_ int sd_journal_get_cursor(sd_journal *j, char **cursor) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!cursor)
                 return -EINVAL;
 
@@ -1005,6 +1023,8 @@ _public_ int sd_journal_seek_cursor(sd_journal *j, const char *cursor) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (isempty(cursor))
                 return -EINVAL;
 
@@ -1104,6 +1124,8 @@ _public_ int sd_journal_test_cursor(sd_journal *j, const char *cursor) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (isempty(cursor))
                 return -EINVAL;
 
@@ -1182,6 +1204,8 @@ _public_ int sd_journal_test_cursor(sd_journal *j, const char *cursor) {
 _public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t usec) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         reset_location(j);
         j->current_location.type = LOCATION_SEEK;
@@ -1195,6 +1219,8 @@ _public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, u
 _public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         reset_location(j);
         j->current_location.type = LOCATION_SEEK;
@@ -1207,6 +1233,8 @@ _public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
 _public_ int sd_journal_seek_head(sd_journal *j) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         reset_location(j);
         j->current_location.type = LOCATION_HEAD;
@@ -1217,6 +1245,8 @@ _public_ int sd_journal_seek_head(sd_journal *j) {
 _public_ int sd_journal_seek_tail(sd_journal *j) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         reset_location(j);
         j->current_location.type = LOCATION_TAIL;
@@ -1236,11 +1266,11 @@ static void check_network(sd_journal *j, int fd) {
                 return;
 
         j->on_network =
-                F_TYPE_CMP(sfs.f_type, CIFS_MAGIC_NUMBER) ||
-                F_TYPE_CMP(sfs.f_type, CODA_SUPER_MAGIC) ||
-                F_TYPE_CMP(sfs.f_type, NCP_SUPER_MAGIC) ||
-                F_TYPE_CMP(sfs.f_type, NFS_SUPER_MAGIC) ||
-                F_TYPE_CMP(sfs.f_type, SMB_SUPER_MAGIC);
+                F_TYPE_EQUAL(sfs.f_type, CIFS_MAGIC_NUMBER) ||
+                F_TYPE_EQUAL(sfs.f_type, CODA_SUPER_MAGIC) ||
+                F_TYPE_EQUAL(sfs.f_type, NCP_SUPER_MAGIC) ||
+                F_TYPE_EQUAL(sfs.f_type, NFS_SUPER_MAGIC) ||
+                F_TYPE_EQUAL(sfs.f_type, SMB_SUPER_MAGIC);
 }
 
 static bool file_has_type_prefix(const char *prefix, const char *filename) {
@@ -1655,6 +1685,7 @@ static sd_journal *journal_new(int flags, const char *path) {
         if (!j)
                 return NULL;
 
+        j->original_pid = getpid();
         j->inotify_fd = -1;
         j->flags = flags;
         j->data_threshold = DEFAULT_DATA_THRESHOLD;
@@ -1816,6 +1847,8 @@ _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!ret)
                 return -EINVAL;
 
@@ -1842,6 +1875,8 @@ _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id12
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         f = j->current_file;
         if (!f)
@@ -1908,6 +1943,8 @@ _public_ int sd_journal_get_data(sd_journal *j, const char *field, const void **
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!field)
                 return -EINVAL;
         if (!data)
@@ -2034,6 +2071,8 @@ _public_ int sd_journal_enumerate_data(sd_journal *j, const void **data, size_t
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!data)
                 return -EINVAL;
         if (!size)
@@ -2084,6 +2123,8 @@ _public_ int sd_journal_get_fd(sd_journal *j) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (j->inotify_fd >= 0)
                 return j->inotify_fd;
@@ -2111,6 +2152,8 @@ _public_ int sd_journal_get_events(sd_journal *j) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         fd = sd_journal_get_fd(j);
         if (fd < 0)
@@ -2124,6 +2167,8 @@ _public_ int sd_journal_get_timeout(sd_journal *j, uint64_t *timeout_usec) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!timeout_usec)
                 return -EINVAL;
 
@@ -2224,6 +2269,8 @@ _public_ int sd_journal_process(sd_journal *j) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         j->last_process_usec = now(CLOCK_MONOTONIC);
 
@@ -2262,7 +2309,10 @@ _public_ int sd_journal_wait(sd_journal *j, uint64_t timeout_usec) {
         int r;
         uint64_t t;
 
-        assert(j);
+        if (!j)
+                return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         if (j->inotify_fd < 0) {
 
@@ -2311,6 +2361,8 @@ _public_ int sd_journal_get_cutoff_realtime_usec(sd_journal *j, uint64_t *from,
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!from && !to)
                 return -EINVAL;
         if (from == to)
@@ -2352,6 +2404,8 @@ _public_ int sd_journal_get_cutoff_monotonic_usec(sd_journal *j, sd_id128_t boot
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!from && !to)
                 return -EINVAL;
         if (from == to)
@@ -2409,6 +2463,8 @@ _public_ int sd_journal_get_usage(sd_journal *j, uint64_t *bytes) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!bytes)
                 return -EINVAL;
 
@@ -2430,6 +2486,8 @@ _public_ int sd_journal_query_unique(sd_journal *j, const char *field) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (isempty(field))
                 return -EINVAL;
         if (!field_is_valid(field))
@@ -2454,6 +2512,8 @@ _public_ int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!data)
                 return -EINVAL;
         if (!l)
@@ -2566,6 +2626,8 @@ _public_ void sd_journal_restart_unique(sd_journal *j) {
 _public_ int sd_journal_reliable_fd(sd_journal *j) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         return !j->on_network;
 }
@@ -2599,6 +2661,8 @@ _public_ int sd_journal_get_catalog(sd_journal *j, char **ret) {
 
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!ret)
                 return -EINVAL;
 
@@ -2636,6 +2700,8 @@ _public_ int sd_journal_get_catalog_for_message_id(sd_id128_t id, char **ret) {
 _public_ int sd_journal_set_data_threshold(sd_journal *j, size_t sz) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
 
         j->data_threshold = sz;
         return 0;
@@ -2644,6 +2710,8 @@ _public_ int sd_journal_set_data_threshold(sd_journal *j, size_t sz) {
 _public_ int sd_journal_get_data_threshold(sd_journal *j, size_t *sz) {
         if (!j)
                 return -EINVAL;
+        if (journal_pid_changed(j))
+                return -ECHILD;
         if (!sz)
                 return -EINVAL;